The DNS looks good. Can you give output for: $ dig mx trendargentina.com.ar. $ dig a mx.trendargentina.com.ar. $ postconf | grep dns
The records that result in some kind of error while delivering to
the mx.trendargentina.com.ar machines. Something like:
$ grep '10\.0\.0\.20..:25' /var/log/maillog | grep -v status=
That's two dots before the ":".
Wietse
